Both line deflection circuits and switched-mode power supplies are increasingly employing higher operating frequencies, for the line deflection for high-definition systems at a line frequency of 32 kHz and for switched-mode power supplies in order to reduce the dimensions of the isolating transformer further. The turn-on and turn-off losses at the switching transistor increase proportionally with the increase in the operating frequency. Efforts are therefore being made to reduce these turn-on and turn-off losses at the switching transistor in order to improve the overall efficiency of the circuit.